Many synthetic smoking products have been described in the art for the purpose of replacing some or all of the tobacco which is conventionally used in smoking products.
Many attempts have been made to utilize cellulosic materials, such as alpha-cellulose, as smoking materials to be used as tobacco replacements or supplements. However, alpha-cellulose and similar materials have, in their untreated form, not been found to be entirely satisfactory materials, either with regard to their burning characteristics or with regard to their smoke properties. Attempts have been made to modify cellulose by oxidative techniques, by heat techniques and by the addition of various materials to modify the properties of the cellulose. Despite these many techniques, cellulose has not been found to be completely satisfactory as a smoking material.
Cellulose has been oxidized by treatment with nitrogen dioxide and similar materials. For example, U.S. Pat. No. 3,461,879 relates to tobacco substitutes in which the combustible portion is oxidized cellulose or is an oxidized material which contains a significant percentage of alpha-cellulose. The theory behind such treatments is believed to involve the oxidation of the primary hydroxyl groups of the cellulose molecule to form carboxyl groups in their place. The oxidation of the cellulose is said to have the effect of reducing the delivery or TPM from the cellulose and to also produce a more desirable taste in the smoke. However, such oxidation, for example with nitrogen dioxide, involves relatively high equipment investment and operation costs and does not produce an entirely satisfactory product.
In addition, various heat treatments have been tried, in attempts to improve the burning properties of cellulose. For example, U.S. Pat. Nos. 3,705,589 and 3,545,448 relate to heat-treated cellulosic materials for use in smoking products. However, the materials produced by such treatments have also not been found to be totally satisfactory.
Some of the synthetic products employ cellulose as a starting material, wherein the cellulose is modified by the addition of certain materials, for example, as is set forth in British Patent 1,113,979.
Compositions which have included certain types of untreated cellulose in combination with other materials, for example, as described in U.S. Pat. No. 3,807,414, have also not been found to provide all of the desired effects.
Other techniques which have been employed have included the heating of cellulosic materials in the presence of a decomposition catalyst in order to obtain a black, brittle material. Furthermore, such black material which has been utilized in powdered form in the manufacture of sheets include chemical binders (for example, as disclosed in South African Patents 73/5352 and 73/5353).
The products which have been made by incorporating various materials in cellulose which has not been thermally treated have not been found to be completely satisfactory in terms of their burning characteristics and in terms of the smoke which is produced upon their combustion.
The products which have involved heating with a decomposition catalyst have also not been completely satisfactory.
The materials involving the oxidation of cellulose to produce oxidized cellulose have been expensive and have produced products which do not resemble tobacco and which have not been found to have totally satisfactory burning characteristics and smoking characteristics.
Other techniques have been described wherein cellulosic materials have been heated at various temperatures in the absence of air. However, these techniques, too, have not provided a totally satisfactory tobacco substitute.
It is also well known in the art that smoking articles may be prepared from a variety of combustible or burnable materials and many materials have been suggested for substitutes or as additives for tobacco. However, such compositions have also not been found to be totally satisfactory.
Many tobacco replacement materials which have been proposed have been made by forming films from slurries or inert and/or combustible materials in combination with synthetic film-forming agents and thereafter cutting or shredding the films to form a smoking product. Various cellulose derivatives, for example, cellulose ethers, such as carboxymethyl cellulose have been suggested for use as the film-forming materials. These cellulose derivatives have been found to differ from cellulose, as well as from pectins or sugars which are naturally present in tobacco. Thus, such cellulose derivatives have been found to introduce new combustion products into the smoke which have not been present in the same amount in conventional tobacco smoke.
Cellulose, itself, is a naturally occurring component of tobacco and is, of course, the main or sole ingredient of the combustible paper wrapper of cigarettes. However, the various items which have been made to utilize cellulose as a smoking material have not been particularly successful, since the quality of the smoke has not been found acceptable unless the cellulose has been subjected to major chemical transformations or has been formulated into compositions with significant amounts of non-cellulosic material. In the instances where the cellulose has been subjected to pyrolytic transformation, the resulting products have often been found to be unsatisfactory in terms of their structure, in terms of being too brittle (for example) to be properly blended with tobacco or to be properly formed into smoking articles. Furthermore, the cellulose which has been produced by pyrolytic transformation has often failed to have the proper smoking properties and burning properties which are desired in the smoking product.
Thus, no completely satisfactory tobacco substitute has been found and it is the object of the present invention to provide an improved smoking product and an improved method of producing the same.
Some of the teachings of the prior art are summarized hereinafter, with patents being presented in numerical order.
U.S. Pat. No. 12,417 relates to the use of cornstalks boiled to make a syrup which is put on leaves of Indian corn as a substitute for tobacco.
U.S. Pat. No. 97,962 relates to the use of eucalyptus leaves using a process of drying, applying hot water or steam, drying, using pressure to crush fibers and then putting into a wrapper to be used as a substitute for tobacco.
U.S. Pat. No. 1,334,752 relates to a fluid for treating tobacco leaves or like plants. The fluid is obtained by boiling resin in a solution of NaCl and by boiling the same in a solution of NaHCO.sub.3 and a solution of organic salt of iron.
U.S. Pat. No. 1,680,860 relates to a smokeable tobacco substitute and process using eucalyptus, adding glycerine or honey or molasses as a hydroscopic agent to prevent drying out of the end product. KNO.sub.3 is used in an aqueous solution to treat leaves to augment flagration of the end product so that it is made useable for cigarettes and for pipe smoking purposes. The leaves are air dried, crushed between rollers, macerated in KNO.sub.3 solution for three hours, drained and put in a pressure vessel at 100.degree.-200.degree. F for 3 hours. The leaves are then compressed and heated up to 212.degree. F, then shredded as filler.
U.S. Pat. No. 2,576,021 teaches that it is known to use wood pulp to make a paper sheet and soak with tobacco extract to make a tobacco substitute and relates to an improvement using fibers of bagasse preferably sugar cane bagasse preferred over wood pulp, cotton, linen, ramie, sisal and other similar fibers because it has a chemical composition similar to tobacco in respect to cellulose, gums, fats and waxes. The process involves washing the sheet and treating it with NaOH or other alkali, and forms a sheet using Fourdrinier equipment. Certain substances can be added to impart desired taste, aroma and color.
U.S. Pat. No. 2,907,686 relates to a tobacco substitute, an elongated cylinder made by charring a piece of wood, to produce charcoal. The wood is charred in the absence of air at 250.degree.-800.degree. C (4-6 hours). The product may include a carrier for flavoring agents, a smoke-forming agent, an ash-forming agent, coating agents, and other materials.
U.S. Pat. No. 2,943,958 relates to tobacco substitutes made from cornsilk and alfalfa. Cornsilk or alfalfa is washed, steamed to leach out solubles (preferably under pressure) and the fibers are treated with aldose, then humidified. The fibers may then be "toasted" at 200.degree.-250.degree. F to brown them.
U.S. Pat. No. 2,943,959 is similar to U.S. Pat. No. 2,943,958 but impregnates the fibers of steamed cornsilk and alfalfa with caffeine. The process involves water washing which may contain a surfactant, e.g. sodium lauryl sulfate or nonylphenoxypolyoxyalkylene glycol, preferably pressure treatment with steam. The materials may contain humectants, e.g. sorbitol, diethylene glycol, triethylene glycol or propylene glycol. Flavoring agents, e.g. vanillin, rum, licorice, and menthol, may also be added.
U.S. Pat. No. 3,034,931 relates to sagebrush as a tobacco substitute. Sagebrush is dried and toasted to a uniform dark color, is also flattened between rollers, is also mixed with materials to enhance color, flavor aroma and burning qualities of the material, e.g. paprika and turmeric, e.g. maple sugar, glycerine, diethylene glycol, e.g. bay leaves, mustard and the like.
U.S. Pat. No. 3,106,209 relates to a tobacco substitute. Vegetable and other leaves, e.g. lettuce, corn, potato, peanut and spinach, are treated with enzymes under controlled humidity. The leaves are treated with SO.sub.2 or NH.sub.3 at 80.degree.-90.degree. F, then brought to 250.degree. F, crushed and then treated with methyl paraban and papain.
U.S. Pat. No. 3,112,754 relates to a tobacco substitute. Various materials may be deposited on a fibrous medium, such as paper or tobacco leaf or the like. Among the materials which may be added in water (preferred solvent) are: fruit juice, e.g. apple juice, caramelized sucrose, cinnamon, vanilla, cloves, tamar, KNO.sub.3 to promote and sustain burning, CaCO.sub.3 as a carrier. The fibrous material may be a natural grown product, e.g. tobacco or rice paper (relatively pure cellulose free of taste). The process comprises mixing the materials at 60.degree.-100.degree. C, forming a suspension and, at 20.degree.-30.degree. C, immersing fibrous material in it.
U.S. Pat. No. 3,255,760 relates to a tobacco substitute. A tobacco extract is deposited on paper formed of non-combustible fibers, e.g. glass fibers. Some natural cellulosic fibers, e.g. beaten wood pulp or even some tobacco leaf may be added.
U.S. Pat. No. 3,323,524 relates to a process which treats many types of leaves to remove certain substances. The leaves are extracted with water at 40.degree.-60.degree. C, followed by a bleach rinse and extraction with an organic solvent, e.g. acetone at 40.degree.-65.degree. C.
U.S. Pat. No. 3,369,551 relates to a tobacco substitute base found by extracting plant leaves with water or an organic solvent with many additives listed. Dried materials are toasted to a golden brown color and treated with appropriate additives.
U.S. Pat. No. 3,447,539 relates to a smoking composition which uses oxidized cellulose as a base.
U.S. Pat. No. 3,461,879 relates to a tobacco substitute constituting oxidized cellulose in combination with a hydrated metal compound, for example, magnesium citrate, hydrated alumina, calcium tartrate or magnesium sulfate.
U.S. Pat. No. 3,478,751 relates to a smoking product made from oxidized cellulose subsequently treated with borohydride.
U.S. Pat. No. 3,478,752 relates to a process for oxidizing cellulose. The description of cellulosic material includes alpha-cellulose, rice paper, gums and plant leaves.
U.S. Pat. No. 3,482,578 relates to a smoking product from oxidized cellulose made by treatment with liquid NO.sub.2, and then treated with borohydride.
U.S. Pat. No. 3,491,776 relates to the selective oxidation of cellulosic material with NO.sub.2.
U.S. Pat. No. 3,512,536 also relates to the selective oxidation of cellulosic material with NO.sub.2.
U.S. Pat. No. 3,529,602 relates to a tobacco substitute using tobacco pectins as a film-forming compound.
U.S. Pat. No. 3,545,448 relates to a smoking material comprising a carbohydrate material, such as cellulose, which is thermally degraded at 100.degree.-250.degree. C until a weight loss of at least 10% has occurred, the degradation taking place in the presence of a strong mineral acid catalyst or in the presence of a salt of such strong acid with a weak base. The patent indicates that especially useful carbohydrate materials include alpha-cellulose, cellulose derivatives such as methyl cellulose, various polysaccharides and various gums.
U.S. Pat. No. 3,556,109 relates to a smoking material made from oxidized cellulose with various salts.
U.S. Pat. No. 3,556,110 relates to a smoking material made from oxidized cellulose with various salts.
U.S. Pat. No. 3,559,655 relates to a smoking material made from oxidized cellulose with various salts.
U.S. Pat. No. 3,575,117 relates to a smoking material made by oxidizing cellulosic material with nitrogen dioxide and treating the resulting material with a peroxide.
U.S. Pat. No. 3,577,994 also relates to smoking materials made by the selective oxidation of cellulose.
U.S. Pat. No. 3,608,560 relates to a smoking material made of oxidized cellulose combined with carbon particles.
U.S. Pat. No. 3,612,063 relates to a smoking material made of oxidized cellulose combined with organic salts of potassium, lithium and copper, such as the oxalic, lactic, glycolic, diglycolic, pivalic or tannic acid salts, and with titanium dioxide.
U.S. Pat. No. 3,631,865 relates to a smoking composition comprising tobacco and certain ammonium salts.
U.S. Pat. No. 3,638,660 relates to a tobacco substitute material prepared from fibrous wood pulp containing at least 90% of alpha-cellulose which is lightly beaten to certain specifications and is then formed into a sheet. Various ammonium compounds and other materials, such as magnesium or potassium salts, may be incorporated in the sheet.
U.S. Pat. No. 3,643,668 relates to a smokable product comprising oxidized cellulose and certain aldehydes.
U.S. Pat. No. 3,702,615 relates to a smokable product made from certain plant leaves, such as lettuce, spinach or cabbage, which are treated by a series of steps to improve their burning characteristics.
U.S. Pat. No. 3,720,660 relates to oxidized cellulose and other polysaccharides, wherein the cellulose is reacted with such materials as strong acids, e.g., H.sub.2 SO.sub.4, with nitrosyl chloride and the like.
U.S. Pat. No. 3,738,374 relates to a tobacco substitute using carbon fibers and an oxidizing agent.
U.S. Pat. No. 3,796,222 relates to a smoking product obtained by treating a slurry of coffee bean hull parts with a reagent, such as diammonium phosphate, to release the pectins contained therein.
U.S. Pat. No. 3,818,915 relates to a smoking product made from a thermally degraded carbohydrate material and containing phenyl acetic acid or 2-phenyl ethanol to mask off notes due to the browning of the carbohydrate.
U.S. Pat. No. 3,874,390 relates to a smokable product formed by heating cellulose to 150.degree.-300.degree. C to obtain a degree of degradation of 5-30% by weight and combining the resulting degraded or carbonized cellulose with an inorganic filler which may be a hydroxide, an oxide or a hydrated oxide of aluminum, iron or silicon, to form a slurry which may then be cast into a sheet for ultimate use as a smoking material.